Gary said,
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Would arc welders, DC motors with brushes, and vacuum cleaners be considered
RF devices from a 2.801 standpoint?
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My read on this is YES - any device that emits RF radiation.
Here in Utah, there was a case where a plastic welding company's equipment
was causing interference to the FM radio band. The FCC stepped in and the
problem was resolved. I know of a case recently in my own neighborhood where
the thermostat on an aquarium heater was causing noise in the amateur radio
bands. The case was resolved amicably between neighbors but the potential
threat of action was there. In that case, the complaint would have been to
the FCC and directed at the manufacturer.